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  • Author: Tamás Nagy x
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Abstract

The Black-winged Stilt was the bird of the year in Hungary in 2019. The population of the species increased from 20–25 breeding pairs to 550–680 pairs from 1980s to the present. 75–85% of the Hungarian population bred on effluent pools for pigs and settling pools at sugar beet factories in the first half of 1990s. There were significantly more breeding pairs in Hungary in 1999 compared to previous years, and finally 871 breeding pairs of Black-winged Stilts were documented in 2000 and the Hungarian population was estimated at 940–960 pairs. There were 550–680 breeding pairs in Hungary between 2015 and 2017. Significantly more clutches had more than five eggs in the sampled colonies during the influx in 2000 than in the egg collections before 1971 or in the sampled colony in 2008 as well. First arrivals reached Hungary between 5 and 20 March (median: 15 March) between 2005 and 2019. These arrival dates fall approximately a month earlier than the former arrival dates in mid-April during the 1980s. 470 Black-winged Stilts were observed in a single flock during post-breeding dispersal, this flock was the largest ever documented in Hungary. Stilts left Hungary by the first half of September in the 1980s, and in contrast, they left Hungary between 27 August and 4 January (median: 19 October) between 2005 and 2019. Recently, the most departure dates fall one and a half to three months later compared to the departure dates in the 1980s. Black-winged Stilts marked in Hungary disperse in the Carpathian Basin during their post-fledging/post-breeding dispersal. Based on ring readings of two individuals, they start to migrate southwest with stopover sites in Italy, but their wintering areas are unknown. Stilts hatched in Portugal (one individual) and France (two individuals) bred in Hungary during the large influxes in 1999 and 2000. Five Black-winged Stilts hatched in Italy were observed later in Hungary and are supposed to be breeders in Hungary in most cases. Furthermore, one individual captured as an adult in Spain and two trapped in Italy were observed in Hungary. The Hungarian population of Black-winged Stilt is threatened by predation on eggs and chicks, drainage of wetlands, and also by human-induced flooding of artificial wetlands (e.g. fishponds). Stilts regularly occupy artificial breeding islands the first years after habitat restoration. The Hungarian population of Black-winged Stilts is increasing due to habitat management with grazing animals, especially with Mangalica ‘Woolly’ Pigs and Water Buffalos.

Abstract

The literature on bird collision with power lines in Hungary is rather limited. We collected published records and carried out research on birds that collided with overhead wires, and we made a list of species, and the number of individuals recorded, around Pusztaszer Landscape Protection Area. The quality of data did not allow us to do robust statistical tests, and a large amount of collected data was not used in this paper, because of uncertainty. Finally, we used the records of 519 individuals of 63 species that got injured or died during collision with overhead wires. We found evidence, that low-, middle- and high-voltage power lines were all responsible for the collision accidents of birds. Birds that use wetlands or both wetlands and farmlands are the most threatened to collide with overhead electric wires. Most victims of collision accidents belong to Gruiformes, Charadriiformes, Pelecaniformes and Anseriformes orders. Our preliminary results suggest that the bigger the rate of weight and wingspan (wing-loading proxy) is, the greater the risk of birds colliding with power lines, probably because of poor manoeuvrability. Birds that move regularly, on a daily basis between their nests/roost sites and foraging areas are at higher risk to collide with electric wires. Our preliminary results do not support the hypothesis that birds which sit on power lines collide more frequently than birds that do not use wires. It seems that foggy weather circumstances increase the probability of collision events particularly in case of Common Cranes. Some large birds were found with burnt feathers after collision with middle-voltage power lines. A sizeable part of collided birds were protected or strictly protected. Bird collision with overhead wires is a serious problem in Hungary. Collision can be stopped on most dangerous part of overhead wires by converting to underground cabling. It is possible to reduce the number of collision events in case of high-voltage power lines by increasing their visibility. We always recommend underground cabling in case of wetlands, if new segments of electric wires would be carried out.

Abstract

Diurnal birds of prey (Accipitriformes and Falconiformes) has traditionally been known as comprising a single order. Recently, this classification has been used in the non-taxonomic sense as referring to a convergent group of birds that are largely classified as predatory birds. Although these birds are similar in their morphology, the species differ in their foraging methods and prey preference. The cranial shape and the physical attributes determine the efficiency of the resource use. The aim of this study is to increase our knowledge of the relationship between skull shape, prey preference, and foraging habits. A geometric morphometric approach was used to analyse two-dimensional cranial landmarks. We used principal component (PC) analyses on measurements that may be related to prey preference and foraging habits. The PCs are resulted described the relative height of the skull and beak, the variation in the relative size, the orientation and robustness of the lacrimal bone, the variation in the relative size of the neurocranium compared to the viscerocranium, and the orientation of the palatine bone. The dietary categories significantly overlap. The skull morphology reflects more on foraging habits than diet or prey preference.

Abstract

Owls (Strigiformes) are small to large birds, mostly solitary and nocturnal predators. They can be found all around the Earth except Antarctica and some remote islands. The species differ in size, diet and habitat, which led to different morphological adaptations of the skull. The main differences are in the orbital and the otical region, which are connected to the visual and hearing capabilities. The aim of the recent study is to increase our knowledge of the relationship between skull shape and foraging habits and tried to find those characters that are related to diet. A geometric morphometric approach was used to analyse two-dimensional cranial landmarks. We used principal component (PC) analyses on measurements that may be related to visual and hearing abilities. The PCs are resulted in the robusticity of the skull and the asymmetry of the otical region. There are differences in position and shape of postorbital processes (POP) and tympanic wings (TW). Species with symmetrical skull shape are basically crepuscular or diurnal predators and species with more asymmetrical skulls are mostly nocturnal hunters and have better hearing capabilities.

Abstract

Parrots (Psittaciformes) are a unique and diverse avian group and vary tremendously in size, shape, and colour. Mainly distributed throughout the tropics and subtropics, most species of parrots are largely or exclusively arboreal with several exceptions. The species also differ in diet and habitat, which led to different musculoskeletal adaptations of the skull. However, parrots have conspicuous generalized external features; in this recent study, we tried to increase our knowledge of the cranial shape and foraging habits. A geometric morphometric approach was used to analyse two-dimensional cranial landmarks. We used principal component (PC) analyses on measurements that may be related to diet. The PCs described the relative height of the cranium, the relative length and curvature of the beak, differences in the orientation and curvature of the lacrimal bone and the upper margin of orbits, variation in the size and position of the palatine bone and the relative width of the cranium, and variation in the relative size of the neurocranium compared to the viscerocranium. The dietary categories overlap in the morphospace but the analysis in lateral and ventral view resulted in significant differences.

Abstract

Though profitable crop production can be more simply achieved by using synthetic pesticides, the research of alternative plant protection solutions is necessary. The effect of the volatile oils of cinnamon, thyme, and a copper ingredient fertilizer were tested for their activity against apple scab and powdery mildew in apple orchards in 2014 and 2017. Oils applied alone or in combination were effective against apple scab in 2014 and in 2017 and against powdery mildew on leaves in 2017. The copper ingredient fertilizer product improved the efficacy of the oils. The results of these trials show that the tested volatile oils are suitable candidates for further research and for the development of organic fungicides against the diseases of apple.

Abstract

This paper proposes and evaluates solutions for an online clustering problem and gives a mathematical model for it. The problem at hand occurs often in the fusion of data streams for example in real time locating systems. The goal is to gather as much incoming information from several sources as possible but also minimize the delay before the next processing step can be executed. The key characteristic is that the data is available in a bursty fashion, in the special case of an RTLS according to the locating cycles. After an introduction of the background a general mathematical model for the problem is given, and then two basic algorithms referred to as NWT and CWT are analyzed by the method of competitive analysis. Each turning out to deliver an optimal solution under different constraints. Then an experimental evaluation follows based on a simulation involving the CWT and the algorithm referred to as VWT. The later is giving a configuration free solution for the problem.

Abstract

Bird conservation on electricity transmission lines has a 40-year history in Hungary. It started with the saker conservation program. The initial small-scale activities were considerably enlarged through the LIFE projects. In the first project, 301 nest boxes for sakers of a new type made of aluminium were installed on pylons of high-voltage transmission lines. In 201 3 nearly 70% of saker pairs nested in these new boxes. An estimated 1 00 000 different birds used to be killed annually on the transmission line pylons in Hungary. During the two LIFE projects about 1 4 300 pylons were made bird-safe using improved technology and materials. Nearly 800 new bird-safe crossarms of pylons are being installed in the second project, which is expected to completely eradicate the danger

Abstract

The shortening of the cervix, cervical incompetence or insufficiency that causes late miscarriage or preterm birth syndrome gives importance and clinical significance for the cervical cerclage or cervical stitch as treatment. Nowadays closure of the cervix with cerclage surgery is an effective way of preventing premature opening of the cervix, helping the pregnancy near due date, thus significantly reducing the risk of miscarriage and premature delivery.

The retrospective longitudinal cohort study is based on an examination of 164 pregnant woman who underwent cervical cerclage surgery at Obstetrics and Gynecology Clinic nr. I Târgu-Mureș, between 2000-2017. The McDonald’s method was used in every case that we have studied.

Cerclage surgery was performed in most cases in the second trimester. The results in the study reflect that in the majority of the cases, intervention is effective in preventing premature opening of the cervix. Most women are multipara and had multiple gestational pregnancy, which can also contribute to the weakening and early opening of the cervical closure system. In 66.5% of the cases, at least one abortion or miscarriage is present in the history of the disease, which may also lead to a weakening of the cervical closing function.

Following cerclage surgery, 11.6% abortion and 88.4% in childbirth occurred, and in most cases, intervention can effectively prevent second trimester abortion while reducing the risk of premature birth (65, 8% had no premature birth in our study).

Abstract

In Dobrogea, a core area for wind energy exploitation in Romania, existing knowledge regarding the intensity and pattern of bird migration is limited. In the absence of enumerated data, wind farms may be constructed in areas where large aggregations of migrants pass. In this study we recorded the intensity of the autumn migration of soaring birds in three locations within the Măcin Mountains, where wind farms are planned to be built. The locations chosen were at Văcăreni, Greci and Cerna villages. Furthermore we categorized all migrating individuals as threatened or non-threatened by the planned wind farms, based on their migration routes and height at local scale. At Văcăreni 4.716 individuals were counted, 3.394 raptors and 1.322 non-raptors, at Greci 2.387 individuals, 2.064 raptors and 323 non-raptors, and finally at Cerna, 5.268 individuals, 4.529 raptors and 739 non-raptors. At all three sites a significant proportion of birds, both raptors and non-raptors, were found to be threatened by the proposed wind farms. At Văcăreni 68.33% of raptors and 84.95% of non-raptors were at threat, at Greci 44.48% and 54.18% respectively, and at Cerna 59.37% and 94.86%. As such we conclude that intensive migration occurs in North Dobrogea and wind farms would have a considerable negative impact on migrants in the studied areas